Tyre maintenance practice What is the primary purpose of rotating tyres on an automobile at regular service intervals?

Introduction / Context:
Tyre rotation is a routine maintenance procedure specified by vehicle manufacturers. Different axle loads, alignments, and drive arrangements cause uneven wear patterns, which rotation seeks to balance over time.

Given Data / Assumptions:

• Front tyres often wear faster due to steering scrub and braking load; drive axle tyres wear from torque transmission.
• Rotation patterns differ for directional, asymmetric, and staggered setups.
• Alignment and inflation remain within recommended ranges.

Concept / Approach:
By periodically changing each tyre's position, the wear is shared among all tyres. This extends tread life, maintains even tread depths, and preserves predictable handling. It does not change construction properties like ply adhesion nor the load index rating.

Step-by-Step Solution:
Assess wear pattern differences between front/rear and left/right.Apply manufacturer's rotation pattern and interval.Result: more uniform wear across all tyres → extended life and consistent performance.

Verification / Alternative check:
Measure tread depth at multiple points before and after several rotations; convergence of depths confirms effectiveness.

Why Other Options Are Wrong:
Ply separation is a manufacturing/overheat issue, not solved by rotation.

“Get better ride” may be a side effect but is not the primary purpose.

Load index is a design rating and cannot be increased by rotation.

Common Pitfalls:
Rotating tyres with unresolved alignment or inflation problems simply migrates abnormal wear; always correct root causes first. Respect directional arrow markings and asymmetric sidewall indications.

Final Answer:
equalize wear